MSefi.com read only forum (Jan.15,2018)

I am planning to MS my 1971 Mercedes 3.5L V8 coupe (213 CID) with existing Bosch D-Jetronic. Researching the stock injectors (Bosch 0280150034) they flow 338 cc/min which seem to be almost twice the size needed for a 230HP engine. Is my thinking correct? They are also low impedance injectors. My questions are:
Should I install smaller Hi Z injectors? Would smaller injectors make tuning easier?
If I use other injectors I would like to use injectors that will directly replace my existing injectors. How could I research this? They use hose and clamp connections. I want to modify my car as little as possible because it is a collectible model.
Thanks
Tony

Tony,

Whether the injectors are too large depends partly on whether you use MS-I or MS-II. MS-II has much more injector pulse width resolution, which helps avoid the idle pulse width problems created by large injectors (http://www.megamanual.com/v22manual/mtune.htm#idlepw).

If you are going to control the ignition timing too, you will need MS-II anyhow. If this was mine, I would keep your current injectors and use MS-II.

Lance.

Thanks for your reply Lance. I am planning on installing EDIS as part of my installation and have had a custom toothed crank wheel fabricated and have all parts.
One reason I was considering using different injectors is that the injectors for my car are rare and expensive and also to preserve my original injectors so I can make the car original if I ever sell it. I spent a little time researching injectors and I found some Mustang 19Lbs injectors that may be ideal. I know others have used Mustang inectors on similar installations. I would need to adapt the fuel connection to my fuel rail since my existing injectors use hose/clamp connections. I have a spare fuel rail I could modify. My car is dissasembled undergoing restoration so it will be awhile before it all comes together.
Look forward to realizing my engines full potential with a modern ignition and fuel system.

After examining the Ford injectors I have found them to be identical to my original injectors with the exception of the pintle cap and the fuel connection. I can build a custom fuel rail-it is preferable to the hose and clamp connections the original injectors use. I removed a pintle cap from one of my original injectors and one of the ford injectors and the pintle is identical so it seems I can install the D-jetronic pintle caps on the Ford injectors and use the seals intended for the D-jet injectors. I have read conflicting information concerning the pressure regulator. Do I need a vacuum controlled regulator or can I use the original reg? I would like to keep as much of the original fuel delivery system as possible.
Thanks

Tony H wrote:After examining the Ford injectors I have found them to be identical to my original injectors with the exception of the pintle cap and the fuel connection. I can build a custom fuel rail-it is preferable to the hose and clamp connections the original injectors use. I removed a pintle cap from one of my original injectors and one of the ford injectors and the pintle is identical so it seems I can install the D-jetronic pintle caps on the Ford injectors and use the seals intended for the D-jet injectors. I have read conflicting information concerning the pressure regulator. Do I need a vacuum controlled regulator or can I use the original reg? I would like to keep as much of the original fuel delivery system as possible.
Thanks

Not much wrong with the hose and clamp connectors - mine are 25 years and some 180,000 miles old. ;-) But later steel pipes can look better.
Are you saying there is no vacuum controlled fuel regulator? That's most unusual.